Washing machine



A. GIL

WASHING MACHINE Nov. 9, 1965 2 Sheets-Sheet 1 Filed Aug. 8, 1963 AR 776A 5 G/L ATTORNEYS United States Patent 3,216,225 WASG MACHINE Artigas Gil, Simon Bolivar Nr. 1424, Piso 2, Apto. Montevideo, Uruguay Filed Aug. 8, 1963, Ser. No. 300,791 3 Claims. (Cl. 68-23) The present invention relates to washing machines, more particularly, to the elimination of undesirable vibrations experienced during the operation of a washing machine having an agitator provided with a combination of reciprocating and rotary motion.

One form of washing machine which is particularly adapted for household use includes a rotatable wash tank having therein a perforated transversely extending partition member which is capable of vertically reciprocating motion. Both the wash tank and this partition member which is essentially an agitator are connected through a transmission to a motor. The transmission is so constructed that this agitator is capable of both rotary and vertically reciprocating movement.

Due to this rotary and reciprocating motion of the several parts of this washing machine, undesirable vibrations are encountered, particularly when the washing machine is unevenly loaded with laundry. These vibrations are particularly objectionable when such a washing machine is being used as a household appliance.

It is therefore the principal object of the present invention to provide a novel and improved washing machine of the type wherein the agitator has a combination of reciprocating and rotary motion.

It is another object of the present invention to eliminate all vibrations in a washing machine having parts capable of reciprocating and/ or rotary motion.

It has been discovered that during the operation of such a washing machine there are three main sources of undesirable vibrations: the mounting between the wash tank and the chassis; the mounting between the drive motor and the chassis; and the rotation of the wash tank with respect to the drive motor. The present invention therefore provides structures to eliminate the vibrations at each of these sources and the combined result of these structures is to produce a largely vibration-free washing machine of this type. It is the coaction of these three vibration absorbing structures which produce a smoothly operating washing machine. While any one of these vibration absorbing structures might be employed alone, it has been determined that these three structures must be present in a washing machine of this type in order to obtain performance which is largely free of vibrations.

In the present invention the improved washing machine comprises a chassis upon Which is rotatably mounted a vertical wash tank. A vertically reciprocable agitator is provided in the wash tank. A drive motor having an output shaft is mounted within the chassis to drive the agitator and to rotate the wash tank. A first feature of this invention comprises a resilient annular member interposed between the chassis and the wash tank so that the wash tank is resiliently mounted thereon.

The second feature for eliminating vibrations comprises a supporting arrangement for the driving motor upon the bottom surface of the chassis.

A third feature of the invention comprises a fluid coupling between the output shaft of the motor and the wash tank so as to regulate the rotary motion of the wash tank.

Other objects and advantages of the present invention will be apparent upon reference to the accompanying description when taken in conjunction with the following drawings, wherein:

FIGURE 1 is a side elevational View of the washing machine of the present invention with a portion of the outer casing cut away and parts of the machine being shown in section;

FIGURE 2 is a vertical sectional view showing the supporting arrangement between the wash tank and the chassis;

FIGURE 3 is an exploded view showing the resilient mounting arrangement between the drive motor and the chassis;

FIGURE 4 is a vertical sectional view of the fluid coupling between the drive shaft and a control shaft which in turn drives the wash tank;

FIGURES 4A and 4B are perspective views illustrating the vane structure on several elements of the fluid coupling shown in FIGURE 4; and

FIGURE 5 is a view similar to that of FIGURE 4 and showing a modified fluid coupling.

With reference to the accompanying drawings, wherein like reference symbols indicate the same parts throughout the various views, a specific embodiment and several modifications will next be described in detail.

With particular reference to FIGURE 1 there is illustrated a washing machine according to the present invention. The washing machine comprises an outer casing or housing 1 supported upon wheels 2. Positioned within the housing is a chassis or supporting frame 3 having a top 4 and a bottom surface 5. A wash tank or tub 6 having sloping side walls is rotatably supported on the chassis 3 in a manner to be presently described. A drive motor 7 having an output shaft 8 is vertically mounted within the chassis 3 in a manner to be described later.

Positioned within the tub 6 is a vertically reciprocable agitator 9 which comprises a mesh net having its periphery attached to the inner surface of the tub 6. The mesh may be woven of a strong yarn and it is preferred to employ a yarn whose filaments are composed of synthetic plastic material since such materials possess the necessary strength and corrosion resistance for this purpose. It can be appreciated that multi-filament strands for a monofilament can be employed to constitute the yarn of the mesh 9. Nylon is a particularly suitable plastic although corrosion resistant wire and other plastic materials can be used. The mesh 9 is held in position by a central hub 10.

Three concentric shafts are provided to connect the tub 6, the agitator 9, and the drive motor 7. These shafts comprise an outer hollow control shaft 11, an inner hollow driving shaft 12, and a driven shaft 13 coaxially positioned within the hollow shaft 11. The control shaft 11 is rotatably supported in the upper end of the chassis 3 by frictionless bearings 14 and has its upper end connected to the tub 6. The driving shaft 12 is rotatably supported within the control shaft 11 by frictionless bearings 15. The output shaft 8 of the motor 7 is connected to a shaft 16 by means of a sleeve 17, and the shaft 16 is fixedly secured to the driving shaft 12.

On the inner surface of the bottom of the tub there is provided a cylindrical extension 18 which is coextensive with the driving shaft 12. The extension 18 has a plate 19 on the upper end thereof, and this plate is provided with a central rectangular or other non-circular opening 20 through which there is slidably mounted the upper portion of the driven shaft 13. This portion of the driven shaft 13 is rectangular or otherwise complementary in shape to the opening 20 in the plate 19. This arrangement prevents relative rotation between the driven shaft 13 and the control shaft 11.

The driven shaft 13 is provided at its lower end with an enlarged portion 21 which is rotatable and slidable within the driving shaft 12. The peripheral surface of the enlarged portion 21 is provided with a reentrant continuous reversing thread 22 of the type well known in the art to obtain reciprocating longitudinal movement.

Patented Nov. 9, 1965 The reversing thread 22 comprises an interconnected left hand and right hand thread shown schematically in FIG- URE 1.

In the wall of the hollow cylindrical driving shaft 12 there is provided a cylindrical housing 23 Whose axis is perpendicular to the axis of the driving shaft 12, with the interior of the housing 23 communicating with the interior of the shaft 12. The outer end of the cylindrical housing, 23 is closed by a cover plate 24 which may be fixed or movable, as desired, for access therein.

Inside of the housing 23 there is mounted a pawl having such a configuration that the pawl 25 will slidab- 1y engage the thread 22 of the driven shaft 13.

From the foregoing description it will be apparent that as the drive motor 7 rotates the driving shaft 12, the pawl 25 will ride in the thread 22 to cause driven shaft 13 to reciprocate, providing however, that the driven shaft 13 rotates at an angular velocity less than the angular velocity of the driving shaft 12. Although the driving shaft 12 is supported with the control shaft 11 by anti-friction bearings 15, rotation of the shaft 12 will tend to rotate control shaft 11 if the shaft 11 is free to rotate. Under normal circumstances, because of the frictionless bearings 15, control shaft 11 will rotate at a smaller angular velocity than the driving shaft 12, and accordingly, driven shaft 13 which is non-rotatable with respect to the control shaft 11 will also rotate at an angular velocity smaller than that of the driving shaft 12.

In order to control the rotation of driven shaft 13, and accordingly the degree of conversion of the rotational movment of driving shaft 12 into the reciprocating motion of driven shaft 13, a suitable structure is provided to selectively control the rotation of the control shaft 11 with respect to driving shaft 12.

Such a structure may comprise a brake shoe (not shown), which engages the exterior of control shaft 11. In some cases it may be desirable to further control the rotation of control shaft 11 with respect to driving shaft 12 in a more positive manner than merely by depending upon the inherent friction of bearings 15. For such cases, clutch means 26 actuated by lever 27, both diagrammatically shown in FIGURE 1, is provided to drivingly interengage control shaft 11 and driving shaft 12. When the clutch is fully engaged, control shaft 11 and driving shaft 12 will rotate together at the same speed. This will cause driven shaft 13 to rotate at the same speed as driving shaft 12. Under these circumstances, driven shaft 13 will not have any reciprocating motion.

The pawl 25 is free to rotate on its axis so that it will constantly engage the thread 22 as the pawl reciprocates with respect to this thread. The pitch of the thread 22 will determine the frequency of reciprocation of the driven shaft 13 with respect to the rotation of the driving shaft 12. By utilizing the clutch 26 and a brake, the conversion of rotational energy of shaft 12 into reciprocating and rotary movement of driven shaft 13 can be readily controlled.

Reciprocation of the driven shaft 13 will not only reciprocate the mesh 9, but also a saucer-shaped plate 28 which is afiixed onto the upper end of the driven shaft 13. A spacer 29 is provided between the upper surface of the plate 28 and the mesh 9. A flexible bellows seal 30 is provided between the under surface of the plate 28 and the bottom of the tub 6 in such a manner so as to enclose the tubular extension 18 and toeliminate any leakage through the bottom of the tub.

As described above, when rotation of control shaft 11 is braked, the entire output of the drive motor 7 will be converted into reciprocation of the driven shaft 13 which in turn reciprocates the mesh 9 through the hub or spacer 29. Upon release of the brake, control shaft 11 is free to rotate and the frictional drag between driving shaft 12 and control shaft 11 is sufficient to effect rotation of the tub 6 which is mounted upon the control shaft 11. A clutch may be utilized in order to effect a more positive connection between control shaft 11 and driving shaft 12. In any event, the rotation of the tub 6 creates sufficient centrifugal force to cause the water to slide upwardly along the sloping walls of the tub and be (113- charged onto a drain pan 31 and out'through drain line 32.

In order to obtain a smooth operating washing machine, particularly when clothes or other laundry become unevenly distributed in the tub 6, several supporting arrangements are provided bewteen various components of the washing machine.

Proceeding next to FIGURE 2, there is illustrated in detail a resilient supporting arrangement between the wash tube and the chassis. This arrangement will absorb longitudinal as well as transverse oscillations which may be transmitted from the tub to the chassis. The supporting arrangement comprises a resilient rubber ring 33 which has a substantially square cross section and is mounted on a flat extension 34 formed on the top of the chassis 3. A metallic ring 35 having a cross section of two U-shaped members at right angles to each other is mounted on the upper surface of the rubber ring 33. The frictionless bearing 14 rotatably supports the control shaft 11 and wash tub 6 from the metallic ring 35. The annular ring 33 will absorb most of the vibrations inherent in washing machines of this type, deriving from the uneven distribution of laundry inside of the wash tub. As a practical matter, the laundry is almost always unevenly distributed within this tub.

A supporting arrangement for eliminating vibrations transmitted by the driven shaft to the driving shaft and then to the driving motor is shown in FIGURES 1 and 3. This arrangement essentially comprises a resilient mounting for the motor upon the chassis.

The mounting arrangement for the motor comprises two inverted U-shaped rubber pads 36 spaced along a horizontal axis passingthrough the vertical axis of the motor 7. The pads 36 are securely attached to the base of the motor in any convenient mannner. A second pair of similar U-shaped rubber pads 37 are mounted on the bottom surface of the chassis and are similarly spaced along a horizontal axis which passes through the vertical axis of the motor 7 but is disposed at an angle of to the first-mentioned horizontal axis. A rubber cross piece 38 connects the rubber pads on the chassis with the rubber pads on the motor. As may be seen in FIGURES 1 and 3, one of the cross arms is received by one pair of rubber pads and the other of the cross arms is received by the other pair of rubber pads. As a result of this construction, the motor 7 is mounted upon the chassis by a floating suspension which rapidly dampens any vibra. tions.

A third element in the vibrating damping system completely eliminates troublesome or undesirable vibrations which would be objectionable to the user of this washing machine. The transmission system described above is capable of distributing the energy of movement between the reciprocating oscillation of the mesh agitator 9 and the rotation of the tub 6 and the entire system connected therewith. A small braking action on the tub 6 is sufficient to restrain the tube so that all of the motion is translated into reciprocating movement and the full beating function of the agitator is obtained. When said braking action is not applied, the tub would rotate at a speed which would depend upon the relative resistances offered to the beating function and-to the rotation respectively. Since these resistances depend largely on the laundry in the tub and its distribution therein, it therefore becomes important to regulate the rotation function.

This regulation is readily accomplished by a turbine fluid coupling illustrated in FIGURES 4, 4A and 4B. The turbine comprises an outer casing 39 which is in the form of a hollow cylinder and is connected to the output shaft 8 of the drive motor 7. There are a plurality of vertically or axially extending vanes 41) on the inner surface of the casing 39. The upper end of the casing 39 is sealed about the control shaft 11 by means of a flexible retainer ring 41 of rubber or the like, which prevents the liquid with which the casing 39 is filled from escaping around the control shaft 11. The liquid contained in the casing 39 is an oil or the like conventional-1y employed in fluid couplings and has sufiicient viscosity in order that this turbine-like fluid coupling is rendered operable.

A second set of vanes 42 are provided on the outer surface of control shaft 11 and are similarly axially positioned. As may be seen in FIGURE 4, clearance is provided between the outer ends of the vanes 40 and 42. When control shaft 11 does not rotate, there is a relative movement between vanes 40 and 42.

When the drive motor 7 is operating and the brake is applied to the tub 6, the action of the turbines requires increasing braking action. This however will result in such a small loss of energy that no drawbacks are apparent in the operation of the system. When the motor 7 is running and the brake is released, the turbine will act as a regulating agent for the rotation of the tub and its influence is felt in such degree that it increases considerably the centrifugation. An immediate effect of the regulation of the rotation is the elimination of possible vibrations which might be produced from a jerking or irregular movement should this occur. If desired, a resilient coupling member 43 may be provided to connect driving shaft 12 with the motor 7.

In FIGURE 5 there is shown a modification of this turbine wherein a control shaft 44 is utilized in place of the casing 39. Axially extending vanes 45 are mounted directly on the outer surface of the control shaft 11 and axially extending vanes 46 are mounted on the inner surface of the control shaft 44. The vanes 45 are continuously rotating and correspond to the vanes 42 of the modification shown in FIGURE 4. A rubber retaining ring 47 is provided to prevent leakage of the liquid contained in this turbine. A resilient sleeve 48 is provided to connect the drive motor 7 with the shaft 12.

While each of the above-described vibration damping structures may be particularly useful by itself for the elimination of particular vibrations, these several structures best mutually cooperate in washing machines wherein the laundry is subjected to a combination of rotational, including oscillatory, and reciprocating motions. While the vibrations referred to will not effect the actual operation of the washing machine, they are nevertheless troublesome and a nuisance to the operator of such Washing machines, particularly when employed as household appliances. The mutual coaction of these three vibration damping systems will virtually eliminate all such troublesome vibrations.

It will be understood that this invention is susceptible to modification in order to adapt it to different usages and conditions and, accordingly, it is desired to comprehend such modifications within this invention as may fall within the scope of the appended claims.

It will also be understood that the above mentioned cross piece 38 may be resilient or not, and of any material whatsoever, rubber or any other.

What is claimed is:

1. In a washing machine, the combination of a chassis having a bottom surface, a vertical wash tank rotatably supported upon said chassis, a vertically reciprocable agitator Within said wash tank, a drive motor having a base and positioned within said chassis, a first pair of resilient pads on the base of said motor and spaced along a horizontal line passing through the vertical axis of said motor, a second pair of resilient pads on said bottom surface of said chassis and spaced along a second horizontal line passing through the vertical axis of said motor but perpendicular to said first horizontal line, a cross-shaped resilient member interposed between said first and second pairs of pads with one arm thereof being engaged by said first pair of pads and the second arm thereof being engaged by said second pair of pads, means drivingly engageable with said motor for rotating said wash tank, and means drivingly engageable with said motor for vertically reciprocating said agitator.

2. In a washing machine, the combination of a chassis, a vertical wash tank rotatably supported upon said chassis, a vertically reciprocab-le agitator within said wash tank, a drive motor mounted on said chassis and having an output shaft, means drivingly engageable with said motor for vertically reciprocating said agitator, means drivingly engageable with said motor and including a control shaft coaxially surrounding said output shaft for rotating said Wash tank, a casing surrounding said control shaft and adapted to contain a liquid therein, said casing being connected to said output shaft, a plurality of axially extending vanes on the inner surface of said casing and a plurality of axially extending vanes on the outer surface of said control shaft with said pluralities of vanes being rotatable past each other to define a fluid coupling.

3. In a washing machine, the combination of a chassis having a bottom surface, a ring of resilient material on the upper surface of said chassis, a frictionless bearing mounted on said resilient ring, a vertical wash tank positioned above said chassis, means on said wash tank for mounting said wash tank on said frictionless bearing whereby said wash tank is rotatably supported on said chassis, a vertically reciprocable agitator within said wash tank, a drive motor having a base and an output shaft and positioned within said chassis, a first pair of resilient pads on the base of said motor and spaced along a horizontal line passing through the vertical axis of said motor, a second pair of resilient pads on said bottom surface of said chassis and spaced along a second horizontal line passing through the vertical axis of said motor but perpendicular to said first horizontal line, a cross-shaped resilient member between said pairs of pads and having one arm being engaged by said first pair of pads and a second arm being engaged by said second pair of pads, means drivingly engageable with said motor for vertically reciprocating said agitator, means drivingly engageable with said motor and including a control shaft coaxially surrounding said motor output shaft for rotating said wash tank, a casing surrounding said control shaft and adapted to contain a liquid therein, said casing being connected to said motor output shaft for rotation therewith, a plurality of axially extending vanes on the inner surface of said casing and a plurality of axially extending vanes on the outer surface of said control shaft with said vanes being rotatable past each other to define a fluid coupling.

References Cited by the Examiner UNITED STATES PATENTS 1,760,775 5/30 Peters 74573 2,171,845 9/39 Cureton 6823 X 2,384,903 9/45 Ferris 68-23 X 2,411,960 12/46 Dyer 6823 X 2,549,756 4/51 Clark 68-23 X 2,577,647 12/51 Clark 6823 X 3,075,404 1/ 63 Wiedemann 248-22 X WALTER A. SCHEEL, Primary Examiner.

WILLIAM I. PRICE, Examiner. 

1. IN A WASHING MACHINE, THE COMBINATION OF A CHASSIS HAVING A BOTTOM SURFACE, A VERTICAL WASH TANK ROTATABLY SUPPORTED UPON SAID CHASSIS, A VERTICALLY RECIPROCABLE AGITATOR WITHIN SAID WASH TANK, A DRIVE MOTOR HAVING A BASE AND POSITIONED WITHIN SAID CHASSIS, A FIRST PAIR OF RESILIENT PADS ON THE BASE OF SAID MOTOR AND SPACED ALONG A HORIZONTAL LINE PASSING RHROUGH THE VERTICAL AXIS OF SAID MOTOR, A SECOND PAIR OF RESILIENT PADS ON SAID BOTTOM SURFACE OF SAID CHASSIS AND SPACED ALONG A SECOND HORIZONTAL LINE PASSING THROUGH THE VERTICAL AXIS OF SAID MOTOR BUT PERPENDICULAR TO SAID FIRST HORIZONTAL LINE, A CROSS-SHAPED RESILIENT MEMBER INTERPOSED BETWEEN SAID FIRST AND SECOND PAIRS OF PADS WITH ONE ARM THEREOF BEING EN- 